1,3-Dipolar cycloaddition reactions of isatin-derived azomethine ylides for the synthesis of spirooxindole and indole-derived scaffolds: recent developments

One‐Pot Three‐Component Synthesis of Quinoxalinone Containing Spiropyrrolidine‐oxindole via 1,3‐Dipolar Cycloaddition with Enhanced Cytotoxicity and Apoptosis Induction in HCT‐116 Cells

“…1,3‐Dipolar cycloaddition reaction has proven to be a highly effective methodology for synthesizing five‐membered heterocyclic compounds via in situ generated azomethine ylides [1,2] . Azomethine ylides, owing to their rich array of functional groups, have demonstrated their versatility as starting materials, for synthesizing a broad spectrum of heterocyclic and physiologically active molecules, [3–5] including spiropyrrolidines via 1,3‐dipolar cycloaddition reaction [6] . Besides, the pyrrolidine core constitutes a crucial part of many natural and synthetic products [7] .…”

Engaging Isatins and Amino Acids in Multicomponent One-Pot 1,3-Dipolar Cycloaddition Reactions—Easy Access to Structural Diversity

“…Given their significant importance in the field of medicine and healthcare, it is unsurprising that these valuable structures have garnered considerable attention from researchers around the world [ 46 , 47 , 48 , 49 , 50 ]. An innovative approach involves multicomponent 1,3-dipolar cycloadditions of azomethine ylides through the decarboxylative condensation of α-amino acids with isatins, which has emerged as a practical tool for creating new spiropyrrolidine oxindole moieties with even more potent therapeutic effects [ 51 , 52 , 53 ]. Noticeably, natural amino acids are abundant and environmentally benign feedstocks for synthetic chemistry.…”

In(OTf)3-catalyzed formal (4 + 3) cycloaddition reactions of 3-benzylideneindoline-2-thiones with 2-indolylmethanols

“…1 synthetic chemists have made substantial efforts to develop novel building blocks and catalytic strategies to streamline the synthesis of these privileged scaffolds. 2 In the past decade, various indole-based molecules, such as vinylindoles, 3 indolylmethanols, 4 indoline-2-thiones, 5 iminoindolines, 6 and others 7 have emerged as powerful two-, three- and four-atom building blocks for the synthesis of structurally diverse indole-fused heterocycles. Among them, the indole-based four-atom building block has attracted the attention of researchers because it provides a straightforward access to indole-fused seven-membered rings via a (4 + 3) cycloaddition.…”